Field of the Invention
The invention is related to a semiconductor device and a manufacturing method thereof, and more particularly, to a semiconductor device having a fin-type structure and a manufacturing method thereof.
Description of Related Art
With the rapid development in semiconductor process techniques, to increase the speed and the performance of devices, the size of the entire circuit device needs to be continuously reduced, and device integrity needs to be continuously increased. In general, in the development trend of a smaller circuit device in semiconductors, the length of the channel region in transistors is also gradually decreasing, so as to increase operating speed of the devices. However, issues such as significant leakage current and short channel effect readily occur to the transistor as a result.
To overcome the above issues, in recent years, industries have proposed a multi-gate structure in which the channel region is sandwiched via a gate, such that the entire channel region is affected by the electric field of the gate and leakage current is reduced as a result. The fin-type field effect transistor is a common transistor having a multi-gate structure. FIG. 1 is a three-dimensional schematic of a known fin-type field effect transistor. Referring to FIG. 1, in a fin-type field effect transistor 10, an oxide substrate 100 has an oxide semiconductor protrusion 102 thereon, a source 104a and a drain 104b are respectively disposed on two opposite ends of the oxide semiconductor protrusion 102, a gate insulating layer 106 is disposed on the oxide substrate 100 and covers the oxide semiconductor protrusion 102, the source 104a, and the drain 104b, and a gate electrode 108 is disposed on the gate insulating layer 106 and across the oxide semiconductor protrusion 102.
However, since the material of the gate electrode is generally a metal material, when the oxide semiconductor material in the fin-type field effect transistor is to be repaired via an oxygen annealing treatment in a subsequent process or the fin-type field effect transistor is in an oxygen environment, oxidation phenomenon often occurs to the gate electrode in contact with oxygen, thus affecting device performance.